<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Document</title>
    <script src="jquery-3.3.1.min.js"></script>
</head>
<body>
<input type="text" id="tel">
<script>
    $('#tel').blur(function(){
        tel=$(this).val();
        $.ajax({
            url:"iap.php",
            type:"get",
            dataType:"json",
            data:{tel:tel},
            success:function(res){

            }
        })
    })
</script>
</body>
</html>